It seems to be a good option to me due to parachutists and spinning blades not getting along particularly well
Fair point, and if it is the operators requirement then clearly you should request start up - his field etc, he can within reason establish whatever local procedures he likes.
However, if that is not the case, and I knew parachuting was taking place, I think I would rather have a quick glance upwards before startup.
I can think of at least one very popular parachuting location where the A/G operator would have no way of seeing whether there was anything above, below or around you to hinder a start so asking would be pretty pointless
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